Manufacturing a base stock from ethanol

Abstract

Methods and a system for manufacturing a base stock from an ethanol stream are provided. An example method includes dehydrating an ethanol stream to form an impure ethylene stream, recovering an ethylene stream from the impure ethylene stream, and oligomerizing the ethylene stream to form a raw oligomer stream. A light olefinic stream is distilled from the raw oligomer stream and blended with the ethylene stream prior to the oligomerization. A heavy olefinic stream is distilled from the raw oligomer stream and hydro-processed to form a hydro-processed stream. The hydro-processed stream is distilled to form the base stock.

The invention claimed is: 
     
       1. A method for manufacturing a base stock from an ethanol stream, comprising:
 dehydrating an ethanol stream to form an impure ethylene stream; 
 recovering an ethylene stream from the impure ethylene stream; 
 oligomerizing the ethylene stream to form a raw oligomer stream; 
 distilling a light olefinic stream, an intermediate olefinic stream and a heavy olefinic stream from the raw oligomer stream and recycling the light olefinic stream to the ethylene stream; 
 alkylating the intermediate olefinic stream to form an alkylated stream; 
 distilling the alkylated stream to form a lights stream and a heavies stream; 
 recycling the lights stream to the intermediate olefinic stream; 
 subjecting the heavy olefinic stream to hydrodemetallation to form a first hydroprocessed stream; 
 subjecting the first hydroprocessed stream and the heavies stream to hydrocracking and/or hydroisomerization to form a second hydroprocessed stream; and 
 distilling the second hydroprocessed stream to form the base stock. 
 
     
     
       2. The method of  claim 1 , wherein said dehydrating the ethanol stream comprises reacting the ethanol stream over an acid catalyst to form ethylene and water. 
     
     
       3. The method of  claim 1 , wherein said dehydrating the ethanol stream comprises reacting the ethanol stream over a zeolite catalyst to form ethylene and water. 
     
     
       4. The method of  claim 1 , wherein oligomerizing the ethylene stream comprises contacting the ethylene stream with a homogeneous catalyst comprising an iron (II) pyridine-bis-imine. 
     
     
       5. The method of  claim 1 , comprising:
 separating an unreacted ethylene stream from the raw oligomer stream; and 
 recycling the unreacted ethylene stream to the ethylene stream. 
 
     
     
       6. The method of  claim 1 , wherein the light olefinic stream comprises light linear alpha olefins. 
     
     
       7. The method of  claim 1 , wherein the heavy olefinic stream comprises heavy linear alpha olefins. 
     
     
       8. The method of  claim 1 , wherein said distilling the second hydroprocessed stream comprises separating a distillate stream, a naphtha stream, or both from the second hydroprocessed stream. 
     
     
       9. The method of  claim 1 , wherein said distilling the second hydroprocessed stream comprises forming a heavy neutral oil stock stream, a medium neutral oil stock stream, or a light neutral oil stock stream, or any combinations thereof.